Styczeń 2021 – Zakład Cząstek i Oddziaływań Fundamentalnych

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 29 stycznia (piątek) o godzinie 10:15, odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Towards spin physics from Lattice QCD”

Referuje: Prof. UAM dr hab. Krzysztof Cichy (UAM)

In this talk, we will present recent directions in lattice QCD computations of nucleon structure, in particular for spin-dependent observables. We will provide a brief non-technical introduction to lattice QCD in general and to lattice methods that give access to the relevant physical quantities. Then, we will review selected results for spin-dependent parton distribution functions (PDFs) and generalized parton distributions (GPDs), including both their moments and their x-dependence. Finally, we will show the nucleon spin decomposition from the lattice in terms of contributions from valence/sea quarks and gluons.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak
prof. dr hab. Jan Królikowski
prof. dr hab. Aleksander Filip Żarnecki

The meeting will take place on zoom.us platform.

Join Zoom Meeting

https://us02web.zoom.us/j/84516096743?pwd=a3BYQ24zY1ZjQTF4eFIwUnM2WlNaZz09

Meeting ID: 845 1609 6743

Passcode: HEP_UW

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 22 stycznia (piątek) o godzinie 10:15, odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Towards identifying the sources of Ultra-High Energy Cosmic Rays”

Referuje: Dr Lech Wiktor Piotrowski (IFD UW)

Even though the first UHECR was detected almost 60 years ago, the origin of these particles remains a mystery. For lower energies, their paths are twisted by the Galactic magnetic field, while for higher energies their fluxes are too low to give a statistically significant location on the sky. This is even though the largest observatories occupy hundreds to thousands of square kilometres.

In this seminar, I will show two approaches to solving this problem. The first one is significantly increasing the volume of the atmosphere observed. This can be achieved either with covering tens of thousands of square kilometres with simple radio antennas, which is the aim of the Giant Radio Array for Neutrino Detection (GRAND) experiment. Alternatively, UHECR induced fluorescent tracks in the atmosphere can be observed from the orbit, which is the idea behind JEM-EUSO and Poemma experiments. The second approach is to detect ultra-high energy neutrinos, unaffected by Galactic magnetic fields, created by the UHECRs close to their origin. This is, again, the aim of both GRAND and Poemma experiments.